In vitro physical properties and clinical stability of reused orthodontic miniscrews: A systematic review and meta-analysis.

Background: While orthodontic miniscrews have been widely documented for their successful application, limited research exists on the stability and effectiveness of reused miniscrews. This systematic review aims to evaluate the stability and effectiveness of reused miniscrews in orthodontic treatments.

Methods: An electronic search was conducted for studies published up to February 2024 across MEDLINE, Web of Science, EMBASE, Scopus, and Cochrane CENTRAL. Additionally, gray literature sources and manual searches of prominent orthodontic journals from 2010 to 2023, were also examined. Studies that investigated the use of miniscrews after retrieval and sterilization involving both in vitro studies and clinical trials were included.

Results: From 946 searched studies, 18 were finally included in our review. Thirteen studies investigated retrieved and sterilized miniscrews, while five examined unused and sterilized miniscrews to isolate the effects of sterilization. After performing a meta-analysis on in vitro studies, no significant difference in insertion, removal, or fracture torque between retrieved and unretrieved miniscrews was found, though sterilized miniscrews had a statistically significant increase in insertion torque without affecting fracture resistance. Meta-analysis of clinical studies revealed that retrieved miniscrews exhibited a significantly higher failure rate with a risk ratio of 0.46 (95% confidence interval = 0.24, 0.69), indicating a higher likelihood of failure on reuse.

Conclusion: There were no significant differences in insertion and fracture torque between new and reused miniscrews. However, reused miniscrews were associated with a higher failure rate. This outcome may be influenced by factors such as sterilization methods, insertion technique, and patient-specific anatomical considerations.